FRIDAY, Oct. 11, 2002 (HealthDayNews) -- If you want to determine your risk for cardiovascular disease, maybe you should throw out your scale and grab the measuring tape.
A study appearing in a recent issue of the American Journal of Clinical Nutrition suggests waist circumference is more strongly associated with cardiovascular risk factors than body mass index (BMI).
"There's been some research that shows that it may not be the total amount of fat in your body but where it is stored. In other words, fat distribution," says Stanley Heshka, a co-author of the study and a research associate at the New York Obesity Research Center at St. Luke's Roosevelt Hospital in New York City.
Body mass index (the measure of body fat based on height and weight) is the most widely used gauge to tell if adults are overweight or obese. The problem is that it doesn't take into account the wide range of fat distribution found in people.
Meanwhile, various studies have found body fat distribution is a better predictor for many diseases.
In the new study, the researchers looked at information on white men and women gathered for NHANES III, the National Health and Nutrition Examination Survey, which collected data on the health and nutrition of 9,019 Americans. Then the researchers correlated BMI values of 25 and 30 (which indicate overweight and obese, respectively) with cardiovascular and diabetes risk factors. They set out to determine what waist circumferences have the same degree of risk for cardiovascular disease and diabetes as the BMI guidelines.
To minimize the risk of heart disease, men should not go above a 35-inch waist and women should not go above 33 inches, Heshka says. Men whose waists are 39 inches or more and women whose waists are 37 inches or more should lose weight -- and inches, he says.
Though the study data involved exquisitely precise measurements (taken just above the top of the hip bone and at the end of a normal exhalation), regular folks don't need to be quite that exact.
If you come close to the recommended cutoff points, though, you need to take them seriously, Heshka cautions.
The researchers are still working to figure out why girth may be a better predictor of risk for cardiovascular disease. It may be because the amount of fat around the waist reflects more fat inside the abdominal cavity, something that has been associated with coronary vascular disease, Heshka says.
Some people have hypothesized that the fat drains into the portal vein and is then distributed to areas most sensitive to the development of cardiovascular disease.
"No one really knows how the fat works," Heshka says.
Heshka is quick to add that waist circumference alone may not be the best measure to determine cardiovascular disease risk.
Heshka and other researchers are now trying to see what combination of measures (for example, height, weight, waist circumference, body frame size
) are the best predictors for the development of cardiovascular disease.
"We may find that waist circumference and BMI in combination have an even stronger association," Heshka says. "That's what the goal is now: To find optimal predictors so we can find those people at risk."
More data is also needed to confirm that people with large waists are also the ones who eventually develop cardiovascular disease.
What To Do
To learn more about cardiovascular disease, visit the U.S. Centers for Disease Control and Prevention (CDC). To calculate your body mass index, visit this CDC site.
